The present invention relates to rigid telescopically arranged multi-cavity dispensing containers for flowable material, such as tooth paste and the like, from which it is desired to dispense simultaneously two or more reactive substances which require separate storage until time of use. More particularly it relates to a disposable refill cartridge, for use in a dispensing container of the above type, which can be used in conjunction with a reusable dispensing head and a reusable base.
There exists a desire to provide sodium bicarbonate and peroxide gel as components of toothpaste. Sodium bicarbonate is a well known and commonly used abrasive and cleaner. Peroxide gel is regarded as a beneficial ingredient to help promote healthy gums. These components are reactive when mixed, and therefore must be maintained separately until time of use.
U.S Pat. Nos. 5,020,694 to Pettengill and U.S. Pat. No. 5,038,963, to Pettengill and Gentile, which are hereby incorporated by reference, disclose rigid piston type multi-cavity dispensing containers for the simultaneous coextrusion in predetermined proportions of two or more materials which may have different rheologies. The lower body member of the containers has a base and two or more piston rods with pistons attached thereto. The upper body member has parallel cylinders for containing the flowable materials and outlet means for dispensing the materials. The lower end of the cylinders receive the pistons whereby the relative compression of upper and lower body members forces the flowable materials out through the outlet means. This produces a single, banded unmixed stream of material that can be neatly and easily applied onto the narrow width of a toothbrush. If, after all of the flowable materials are expended, the upper and lower members are pulled apart, the piston heads remain attached to the piston rods of the lower member. Thus any upper body refill unit would not come equipped with pistons to seal the flowable materials within the upper body parallel cylinders. Such a refill unit would be messy and impractical. Accordingly, both upper and lower body members of these designs are discarded after the contents of dispenser are used up. This produces unnecessary waste and is not the most economical of arrangements.
U.S. patent application Ser. No. 07/901,670, to Gentile, which is hereby incorporated by reference, discloses a multi-cavity dispensing refill cartridge to be used with a reusable base. The refill cartridge has two hollow, separate parallel cylinders for containing flowable material. One end of each cylinders is in fluid communication with outlet means while the other end telescopically and slidingly accommodate piston heads. A reusable base with piston rods is used to compress piston heads in the refill cartridge thereby dispensing the flowable material. Once the flowable material is expended, the refill cartridge can be discarded and a new one can be used with the reusable base. While this design is more environmentally friendly than past designs, there is still room for improvement. In particular, because the refill cartridge of the '670 application contains the means for dispensing the flowable materials (i.e. outlet assembly, nozzle, cap and a rigid dispensing head to be pressed upon in the dispensing of the flowable material) more material than is absolutely necessary is discarded each time the refill cartridge is replaced.
Thus it is an object of this invention, for ecological and economical reasons, to provide a multi-cavity dispensing refill cartridge which can be used in conjunction with a reusable base and a reusable dispensing head, for the simultaneous coextrusion, in predetermined portions, of two or more flowable materials, which may have different rheologies, upon the relative compression of the reusable dispensing head and the reusable base, to produce a single, banded unmixed stream of material that can neatly and easily be applied onto the narrow width of a toothbrush. It is a further object to provide such a refill cartridge which, in conjunction with the reusable base and reusable dispensing head, dispenses a single stream of unmixed material and which provides segregation of the component materials within the dispenser both prior to and after dispensing.